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Active Substance: filgrastim
Common Name: filgrastim
ATC Code: L03AA02
Marketing Authorisation Holder: Sandoz GmbH
Active Substance: filgrastim
Status: Authorised
Authorisation Date: 2009-02-06
Therapeutic Area: Neutropenia Hematopoietic Stem Cell Transplantation Cancer
Pharmacotherapeutic Group: Immunostimulants

Therapeutic indication

  • Reduction in the duration of neutropenia and the incidence of febrile neutropenia in patients treated with established cytotoxic chemotherapy for malignancy (with the exception of chronic myeloid leukaemia and myelodysplastic syndromes) and reduction in the duration of neutropenia in patients undergoing myeloablative therapy followed by bone-marrow transplantation considered to be at increased risk of prolonged severe neutropenia. The safety and efficacy of filgrastim are similar in adults and children receiving cytotoxic chemotherapy.
  • Mobilisation of peripheral blood progenitor cells (PBPC).
  • In children and adults with severe congenital, cyclic, or idiopathic neutropenia with an absolute neutrophil count (ANC) of ≤0.5 x 109/l, and a history of severe or recurrent infections, long term administration of filgrastim is indicated to increase neutrophil counts and to reduce the incidence and duration of infection-related events.
  • Treatment of persistent neutropenia (ANC ≤ 1.0 x 109/l) in patients with advanced HIV infection, in order to reduce the risk of bacterial infections when other therapeutic options are inappropriate.

What is Zarzio?

Zarzio is a solution for injection or infusion (drip into a vein) in a prefilled syringe. It contains the active substance filgrastim (30 or 48 million units).

Zarzio is a ‘biosimilar medicine'. This means that Zarzio is similar to a biological medicine that is already authorised in the European Union (EU) and contains the same active substance (also known as the ‘reference medicine’). The reference medicine for Zarzio is Neupogen. 

What is Zarzio used for?

Zarzio is used to stimulate the production of white blood cells in the following situations:

  • to reduce the duration of neutropenia (low levels of neutrophils, a type of white blood cell) and the occurrence of febrile neutropenia (neutropenia with fever) in patients receiving chemotherapy (cancer treatment) that is cytotoxic (cell-killing);
  • to reduce the duration of neutropenia in patients undergoing treatment to destroy the bone marrow cells before a bone-marrow transplant (such as in some patients with leukaemia) if they are at a risk of long-term, severe neutropenia;
  • to increase levels of neutrophils and reduce the risk of infections in patients with neutropenia who have a history of severe, repeated infections;
  • to treat persistent neutropenia in patients with advanced human-immunodeficiency-virus (HIV) infection, to reduce the risk of bacterial infections when other treatments are not appropriate.

Zarzio can also be used in people who are about to donate blood stem cells for transplant, to help release these cells from the bone marrow. The medicine can only be obtained with a prescription.

How is Zarzio used?

Zarzio is given by injection under the skin or infusion into a vein. How it is given, the dose and the duration of treatment depend on why it is being used, the patient’s body weight and the response to treatment. Zarzio is usually given in a specialised treatment centre, although patients who receive it by injection under the skin may inject themselves once they have been trained appropriately. For more information, see the package leaflet.

How does Zarzio work?

The active substance in Zarzio, filgrastim, is very similar to a human protein called granulocyte colony stimulating factor (G-CSF). Filgrastim is produced by a method known as ‘recombinant DNA technology’: it is made by a bacterium that has received a gene (DNA), which makes it able to produce filgrastim. The replacement acts in the same way as naturally produced G-CSF by encouraging the bone marrow to produce more white blood cells.

How has Zarzio been studied?

Zarzio was studied to show that it is comparable to the reference medicine, Neupogen.

Four studies looked at the levels of neutrophils in the blood in a total of 146 healthy volunteers who received Zarzio or Neupogen. The studies looked at the effects of single and repeated administration of various doses of the medicines, either injected under the skin or infused into a vein. The main measure in these studies was the neutrophil count over the first 10 days of treatment.

What benefit has Zarzio shown during the studies?

Zarzio and Neupogen brought about similar increases in blood neutrophil counts in healthy volunteers over the course of the studies. This was considered sufficient to demonstrate that the benefits of Zarzio are comparable to those of the reference medicine.

What is the risk associated with Zarzio?

The most common side effect with Zarzio (seen in more than 1 patient in 10) is musculoskeletal pain (pain in the muscles and bones). Other side effects may be seen in more than 1 patient in 10, depending on the condition that Zarzio is being used for. For the full list of all side effects reported with Zarzio, see the package leaflet.

Zarzio should not be used in people who may be hypersensitive (allergic) to filgrastim or any of the other ingredients.

Why has Zarzio been approved?

The Committee for Medicinal Products for Human Use (CHMP) decided that, in accordance with EU requirements, Zarzio has been shown to have a comparable quality, safety and efficacy profile to Neupogen. Therefore, the CHMP’s view was that, as for Neupogen, the benefit outweighs the identified risk. The Committee recommended that Zarzio be given marketing authorisation.

Other information about Zarzio

The European Commission granted a marketing authorisation valid throughout the EU for Zarzio to Sandoz GmbH on 6 February 2009.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.